Awesome 12X Chrome Pen

I recently put together a 12X laser in a chrome Leadlight pen. I am powering it with a pair of Sanyo 1000mAh NiMH AAA batteries.

Components:

• Leadlight chrome pen
• 12X diode (SF-BW512?)
• Micro FlexDrive V5
• 405-G-1 lens
• Aixiz/Aluminum module
• Optical fiber

To start off the construction, I drilled out a hole through the Aixiz module for the fibers, pressed in the diode, set the driver, soldered it directly to the diode, and attached the switch to the driver input.


Next, I prepared an aluminum heat-sink. The back of the Aixiz module does provide some improvement for heat transfer from module to host, but I chose aluminum since this was planned to be a high output laser and about 1.4W of heat will need to be moved as quickly as possible. The threads on the Aixiz module were removed so that it could be pressed into the aluminum heat-sink. The heat-sink has an inner diameter of ~9.5mm so the FlexDrive can fit easily.
After the heat-sink was ready, I started stuffing the fibers into the module.


I don't like to leave the hole for the LED indicator unused so I use the laser's own output to make the "LED indicator" with fiber optics. With the 405nm laser, it is possible to put a little dab of fluorescent fabric paint over the end of the fibers in the indicator so that it glows (and is visible through safety goggles) but I like the violet light better. Here it is powered up for the first time.


After the fibers were installed and everything was pressed together nicely, I set up the switch on a PCB stripped of its components and epoxied it to the back of the module to keep it fixed.
With the module completely assembled, it was time to begin testing it out.
The Aluminum heat-sink was carefully prepared with some holes drilled through it in order to make it possible to thread the fibers through and to adjust the driver after the module was pressed together.


Tip: When assembling compact lasers with minimal heat-sinking mass, I find that it is best to set the current to the desired range and then test the module observing how much heat it is producing and at what rate. If it gets hot too quickly, reduce current slightly until you can operate the module with a reasonable duty cycle. If you feel the module isn't hot enough, increase the current slightly. This ensures that you are getting the most power possible without exceeding the heat-sinking capacity of your host allowing you to get a duty cycle that agrees with the intended use of your laser.

Next, I pressed the module into the pen host and was ready to lase.

The last photo includes a 50mW 405nm for comparison.

After carefully adjusting the current, I ended up with a nice, stable output of 475mW +/-5. For 405nm laser diodes, the 405-G-1 is the absolute best lens to use! It is simply a must!


I spent the past couple days trying to get some nice photos to show off this laser.
I hope you like 'em. If you would like to know the Exif Info. I would be glad to provide it.



In the above photos I was shooting at 1/500sec. to capture the ignition of some flash paper and matches.



I was hoping to get some shots with some stars but the past few nights have been too humid and hazy. I improvised and got a few good shots of the beam terminating on the cloud cover.

Here is the extended power test video:


Any questions or comments are welcome.

That's nice man good job.
Does it get warm?

Very nice build tutorial!!
I love the micro builds like this one, and the sleek silver host is great!

Great to see that you haven´t cancelled the laser-hobby.

Well done review. Your pics are awesome. Haven´t seen better for a long time.

Awesome work Once again.:gj:

I have a question for you. DO you drill out the apercher hole at all.?

Because i have one but i have a red laser in it and i did not drip out the aperture larger to allow the full beam to come out so there is scatter around the dot for the first 10 feet or so.

I was going to take it apart to make the aperture larger but i got to admit although the dot really doesn't look all that great up close the beam is flat out Epic. Its a nice round solid skinny beam.

I love these pens. Especial with the LED Indicator light.

The Fiber optic wire is brilliant.!!!

+:beer:

Hi Daniel, Very nice build and photos, I really like

One question, ¿why you've been so conservative with the power output?

I think with these 12x diodes you can get perfectly without forcing the diode 600mW output at 400mA approx.

Is perhaps a restriction on the heat-sink or other?

Thanks.

That's a superb pen build, and I like your photography.

+1

lazeerer said:

Awesome work Once again.:gj:

I have a question for you. DO you drill out the apercher hole at all.?

Because i have one but i have a red laser in it and i did not drip out the aperture larger to allow the full beam to come out so there is scatter around the dot for the first 10 feet or so.

I was going to take it apart to make the aperture larger but i got to admit although the dot really doesn't look all that great up close the beam is flat out Epic. Its a nice round solid skinny beam.

I love these pens. Especial with the LED Indicator light.

The Fiber optic wire is brilliant.!!!

+:beer:

Click to expand...

No, I do not drill out the aperture. If you are using the 650-G-1 lens for your red laser, the beam will be quite a bit thinner and more gaussian instead of uniform like the Aixiz glass lenses.
Because of the difference in beam profile, the aperture will cut off any splash from the diode when using the 650-G-1 lens while allowing the rest of the beam to exit unhindered.

This one uses the 405-G-1 lens rather than the Aixiz glass and the same thing applies. Thinner beam means no need to drill out the aperture and more power.

piferal said:

Hi Daniel, Very nice build and photos, I really like

One question, ¿why you've been so conservative with the power output?

I think with these 12x diodes you can get perfectly without forcing the diode 600mW output at 400mA approx.

Is perhaps a restriction on the heat-sink or other?

Thanks.

Click to expand...

Yes, the 12X diode can produce much more power. However, the diode I have is not super efficient (just a little over 1:1 output to current ratio) and produces ~500mW at 400mA. But the main limiting factor here was the heat produced.
Currently, the diode is running at approximately 350mA and taking about 5.77V. Excluding the heat produced by the 5-15% inefficiency of the FlexDrive, the total heat produced by the diode is about... 1.5W which is a little more than my original guesstimate of 1.4W.
Normally, I consider 1.3W of heat from the diode the limit for pens but this 12X is doing fine with the Aluminum heat-sink (compared to using either brass or the back of the Aixiz which is also brass). As I stated above, I carefully adjusted the current so that I could get the max power without exceeding the limits of the host.
It does get warm with continuous use so I keep it to a 90 sec. duty cycle. This is slightly lower than the 2-3 minute continuous operation I normally aim for, but for some of the photos I took the laser was on continuously for about 5 minutes at a time. The nights have been cool so it was not a problem. 475mW is plenty of power IMO, since I don't really like Class IV portables very much. I hardly ever use my 445nm at 1.3W. It's just too much power to feel comfortable playing with. If I leave it pointed in any one direction for more than an instant, whatever the beam terminates on starts to burn up.

@Everyone else, thanks for the compliments!
I will probably have some more interesting beam shots up later when I have an opportunity to try out something new.

Nice build Daniel( good to know your name ) I still doubt though that it can stand the heat produced :/

So you used diode's own output, transfered via optical fiber from between the diode and lens space, as an LED indicator of emission on outside of *PEN* host...



Hat off, plus rep, good god-damned job!!

Silvershot said:

Nice build Daniel( good to know your name ) I still doubt though that it can stand the heat produced :/

Click to expand...

I am uploading a power test video to put your skepticism to rest. Please check the first post and let me know what you think.

Eudaimonium said:

So you used diode's own output, transfered via optical fiber from between the diode and lens space, as an LED indicator of emission on outside of *PEN* host...

Click to expand...

Yes.
It's not the first either. I made a set of these a while back... 445nm 150mW, SF-AW210 175mW, and a LOC 300mW. Plus my trusty DIY chrome greenie. I didn't keep them for very long though. Except for the 300mW red which I sold a couple weeks ago. I still have the greenie, too. It's one of my favorites.

Simply amazing build and great photography as always. I wish I could that lol..

Very nice build dude!!
I recently finish my 445 1W with this host too.
The host is very sweet.

Very Cool build, over the top for a laser of this size

Wow that 12x pen is very nice, that output is very stable for an extended run like that and very well thought out. I enjoyed listening to your vid as much as wathcing it :beer:

Just wanna add I have this laser now and it still works strong.I've had it since he sold it and that was like almost 4 years ago. It still has the same output and I've used it while engraving for over 2 minutes and it never died. If you use it with a fan there's not even no heat. Truly an amazing build.